There is $10$ units of charge at the centre of a circle of radius $10\,m$. The work done in moving $1\,unit$ of charge around the circle once is...........$units$.

The equation of an equipotential line in an electric field is $y = 2x$. The electric field strength vector at $(1, 2)$ may be:

There is a uniform electric field of intensity $E$ as shown in the figure. How many labelled points have the same electric potential as the fully shaded point?

The work done to move a charge on an equipotential surface is

The figure shows two parallel equipotential surfaces $A$ and $B$ kept a small distance $r$ apart from each other. $A$ point charge of $q$ coulomb is taken from the surface $A$ to $B$. The amount of net work done will be

Positive and negative point charges of equal magnitude are kept at $(0, 0, a/2)$ and $(0, 0, -a/2)$,respectively. The work done by the electric field when another positive point charge is moved from $(-a, 0, 0)$ to $(0, a, 0)$ is